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The attitude of AO-73 / FUNcube-1 is passively stabilised using the traditional magnet and two hysteresis rods. Since the launch over four years ago we have been intrigued with the resultant actual spin rate/period which seems to vary over time for reasons that have not yet been properly explained.

This graphic, which has been developed from telemetry received and maintained by Colin, VK3IH, and his team, shows the variations in some detail. Explanations would be gratefully received.

Mike, DK3WN’s, illum.exe software showing predicted duration of the first period

As it is expected that illumination levels may be having an influence, the next few months and years will prove interesting. The spacecraft will be entering periods of continuous sunlight. Initially this will be for a six-week period but then for periods of up to nine months!

Today, November 21st 2017, marks the fourth birthday for FUNcube-1 (AO-73) in orbit.

FUNcube-1 was launched at 07:10 UTC on November 21st 2013 and its first signals were received immediately after deployment over the Indian Ocean by amateurs in South Africa. Since then it has been operating continuously in either its education mode or, with the transponder active, in amateur mode when in eclipse and at weekends.

AMSAT-UK FUNcube Mission Patch

The spacecraft has spent the four years in space orbiting the earth at between 640 and 580 km and has now traveled around the earth more than 20,000 times. That represents a distance traveled of approaching 500 million miles.

Up to now, each of the orbits has been spilt approximately 65% in sunlight and 35% in eclipse. This has resulted in the temperatures inside the small spacecraft varying by about 25° C during each orbit.

During the recent AMSAT-UK Colloquium, Wouter Weggelaar, PA3WEG, in his presentation about the FUNcube project mentioned that the power available from the solar panels has been slowly increasing since launch. This observation led the team to do some further investigations as to the cause.

Although the launch was into a nominally Sun Synchronous orbit, over time this has drifted and the spacecraft is now entering a period when it will be in the sun for longer periods during each orbit. The exact details are still being determined, but it seems likely that, starting from January 2018, there will be periods when the spacecraft will be in the sun for all, or almost all, of its orbits.

FUNcube-1 temperature rise

This means that the on-board temperatures will be much higher than we have previously experienced in flight, although we have some test records from pre-flight thermal air testing that were undertaken after integration.

The key will be to discover what the equilibrium temperature will be internally. For comparison, AO85 has already “enjoyed” periods of full sun and its internal temperatures have reached up to around 55° C.

So the next few months will be quite an exciting time for the team! We remain extremely grateful to everyone is using the spacecraft for both its educational and amateur missions. Of course we are also very very grateful to those who are downloading the telemetry and uploading the data to the Data Warehouse. It continues to provide a unique record of “life on board” a 1U CubeSat in space.

Following a picture-perfect launch, RadFxSat was deployed at 11:09 UTC. Then the wait began. At 12:12 UTC, the AMSAT Engineering team, watching ZR6AIC’s WebSDR waterfall, saw the characteristic “Fox Tail” of the Fox-1 series FM transmitter, confirming that the satellite was alive and transmitting over South Africa. Shortly after 12:34 UTC, the first telemetry was received and uploaded to AMSAT servers by Maurizio Balducci, IV3RYQ, in Cervignano del Friuli, Italy. Initial telemetry confirmed that the satellite was healthy.

After confirmation of signal reception, OSCAR Number Administrator Bill Tynan, W3XO, sent an email to the AMSAT Board of Directors designating the satellite AMSAT-OSCAR 91 (AO-91). Bill’s email stated:

“RadFxSat (Fox-1B) was launched successfully at 09:47 UTC today November 18, 2017 from Vandenberg Air Force Base in California and has been received by several amateur stations.

RadFxSat (Fox-1B), a 1U CubeSat, is a joint mission of AMSAT and the Institute for Space and Defense Electronics at Vanderbilt University. The Vanderbilt package is intended to measure the effects of radiation on electronic components, including demonstration of an on-orbit platform for space qualification of components as well as to validate and improve computer models for predicting radiation tolerance of semiconductors.

RadFxSat (Fox-1B) signal received at 12:12 GMT, Nov 18 by the ZR1AIC WebSDR in South Africa

AMSAT constructed the remainder of the satellite including the spaceframe, on-board computer and power system. The amateur radio package is similar to that currently on orbit on AO-85 with a FM uplink on 435.250 MHz (67.0 Hz CTCSS) and a FM downlink on 145.960 MHz. Experiment telemetry will be downlinked via the DUV subaudible telemetry stream, which can be decoded using the FoxTelem software.

RadFxSat (Fox-1B) was sent aloft as a secondary payload on the United Launch Alliance (ULA) Delta II rocket that will transport the Joint Polar Satellite System (JPSS)-1 mission. RadFxSat (Fox-1B) is one of four CubeSats making up this NASA Educational Launch of Nanosatellites (ELaNa) XIV mission, riding as secondary payloads aboard the JPSS-1 mission.

Since RadFxSat (Fox-1B) has met all of the qualifications necessary to receive an OSCAR number, I, by the authority vested in me by the AMSAT President, do hereby confer on this satellite the designation AMSAT-OSCAR 91 or AO-91. I join amateur radio operators in the U.S. and around the world in wishing AO-91 a long and successful life in both its amateur and scientific missions.

I, along with the rest of the amateur community, congratulate all of the volunteers who worked so diligently to construct, test and prepare for launch the newest amateur radio satellite.

William A. (Bill) Tynan, W3XO
AMSAT-NA OSCAR Number Administrator”

The FM voice transponder was made available for amateur use on November 23, 2017.

Get FoxTelem set up and ready to go on Saturday! The first amateur radio operator that successfully receives RadFxSat (Fox-1B) telemetry and uploads it to the AMSAT server will receive a commemorative 3D printed QSL card.

RadFxSat is scheduled for launch at 1:47am PST (09:47 UT) on Saturday, November 18 from Vandenberg Air Force Base, California. The first transmission from RadFxSat is expected to occur around 12:07 UT. Due to a lack of prelaunch Keplerian elements, it is not known exactly where the satellite will be when it makes it’s first transmission.

The Chertsey Radio Club got some good publicity for both amateur radio and the FUNcube-1 (AO-73) satellite in the Heathrow Villager newspaper published on November 4, 2017.

Club members James Preece M0JFP, Ian Parbery 2E0IPP and Bob Conduit M6FLT along with the 6th Staines Scout Group ran a Jamboree On The Air (JOTA) station GB6SS.

During the event the FUNcube-1 satellite transmitted a special Fitter Message from Space that the Scouts successfully decoded, it said:“ChertseyRC: GB6SS have fun celebrating 60 years of JOTA 6th Staines Scouts, Cubs and Beavers 20 Oct 17”

RadFxSat (Fox-1B) is scheduled for launch on Saturday, November 18, 2017 at 09:47 GMT. RadFxSat is one of four CubeSats making up the NASA ELaNa XIV mission, riding as secondary payloads aboard the Joint Polar Satellite System (JPSS)-1 mission. JPSS-1 will launch on a Delta II from Vandenberg Air Force Base, California.

RadFxSat is a partnership with Vanderbilt University ISDE and hosts four payloads for the study of radiation effects on commercial off the shelf components. RadFxSat features the Fox-1 style FM U/v repeater with an uplink on 435.250 MHz (67.0 Hz CTCSS) and a downlink on 145.960 MHz. Satellite and experiment telemetry will be downlinked via the “DUV” subaudible telemetry stream and can be decoded with the FoxTelem software https://www.amsat.org/foxtelem-software-for-windows-mac-linux/

Launch and Early Orbit Phase (LEOP)

RadFxSat will launch at 01:47 PST (09:47 UTC) on Saturday, November 18, 2017 from Vandenberg Air Force Base, California. At this time, pre-launch Keplerian elements are not expected to be available. However, based on the Local Time of the Ascending Node (LTAN) of the primary payload, 13:30, stations should expect to have their initial ascending passes starting around noon local time. The estimated time of “First Veronica,” the initial beacon after deployment, is 12:07 UTC. Due to the tight constraints on the primary payload deployment, the secondary payloads may be delayed slightly, so this should be considered the soonest the transmitter will be enabled. Orbital elements will be published as soon as they are available on the AMSAT website. Stations in Europe, South America, and North America should point your beams south and have FoxTelem running while awaiting the initial post-launch Keplerian elements.

Participation in telemetry collection by as many stations in as many parts of the world as possible is essential as AMSAT Engineering looks for successful startup and indications of the general health and function of the satellite as it begins to acclimate to space.

If you are capturing telemetry with FoxTelem please be sure that “Upload to Server” is checked in your settings, and that your “Ground Station Params” are filled in as well. You can help AMSAT and everyone waiting to get on the air with RadFxSat tremendously by capturing RadFxSat telemetry.

About 60 minutes after deployment, or 140 minutes after launch, the satellite will start up in Beacon Mode. In this initial mode, the transmitter is limited to 10 seconds on time and then will be off for
two minutes. For those of you capturing telemetry, that means that you will only see Current frames and no High or Low frames. The High and Low frames are truncated as it takes just over the 10 second limit to send two frames. Veronica may also be cut off before she gets to say her whole ID string as the full ID, “RadFxSat Fox-1B Safe Mode,” is a bit longer than the approximately 3.5 seconds she has in Beacon Mode. If the voice ID is cut off, the satellite is still in Beacon Mode.

If AMSAT Engineering is seeing nominal values from the telemetry you gather, the satellite will be commanded from Beacon Mode to Safe Mode on the first good pass over the United States. In Safe Mode, the satellite transmits a full two frames of telemetry (one Current frame followed by, and alternating each ID cycle, a High or a Low frame). Veronica now has time to make the whole ID announcement in Safe Mode.

The on-orbit checkout procedure for RadFxSat is similar to Fox-1A/AO-85 and could be completed in as little as a few days if users cooperate. It is very important, and good amateur operating practice, to refrain from using the transponder uplink so the on-orbit tests can be performed, including when the satellite is switched into Transponder Mode for testing.

AMSAT will make it broadly known when the tests are complete and the transponder is available for all to use. If you hear someone on the transponder, please do not assume that it is open for general use – check AMSAT’s website, Facebook, and Twitter before transmitting to be sure you do not interfere with testing.

AMSAT asks all satellite operators to contribute just a little bit of your time by gathering telemetry, not using the transponder uplink, to help complete the last few days of getting RadFxSat operating for the amateur radio community.

Lots of hams put thousands of volunteer hours of their time into making RadFxSat happen. Just like any ham radio project you might undertake, AMSAT builds satellites. AMSAT volunteers do it because they like to, and when they are done, AMSAT freely shares their project with hams everywhere as is the spirit of amateur radio.